/Engine/Source/Runtime/MeshDescription/Public/MeshDescription.h
Return the vertex instance which corresponds to the given vertex on the given triangle, or INDEX_NONE
[FVertexInstanceID](API\Runtime\MeshDescription\FVertexInstanceID) GetVertexInstanceForTriangleVertex ( const [FTriangleID](API\Runtime\MeshDescription\FTriangleID) TriangleID, const [FVertexID](API\Runtime\MeshDescription\FVertexID) VertexID ) const